CN108495700A

CN108495700A - Supporting layer for forward osmosis membrane

Info

Publication number: CN108495700A
Application number: CN201680079931.2A
Authority: CN
Inventors: 胡马云·穆阿德尔; 约翰·查尔斯特; 迭戈·阿马多-托里斯
Original assignee: Oasys Water Inc
Current assignee: Oasys Water Inc
Priority date: 2015-11-24
Filing date: 2016-11-23
Publication date: 2018-09-04
Also published as: US20200114317A1; WO2017091645A1

Abstract

The method that the present invention relates generally to forward osmosis membrane and makes forward osmosis membrane, the thin supporting layer of improvement for active layer of particularly casting on it.

Description

Supporting layer for forward osmosis membrane

Technical field

One or more aspects relate generally to the film for permeability and separation technique.More particularly, one or more aspects It is related to being improved film supporting layer, with the permeability and separation technique of optimization design.

Background technology

Property substantially liquid permeable and substantially impermeable solute of the semipermeable membrane according to its selective resistance block material. Osmotic drive UF membrane generally passes through one or more supporting layers of the film used in separating technology by with solute is driven The associated driving force in channel.

The polymer film used in liquid separation is typically laminated film (TFC), and laminated film is typically included in porous branch Selective resistance block material on support structure.The exploitation of nearest highly selective film focuses primarily upon reverse osmosis (RO) technique.It is reverse osmosis It is a kind of pressure-driven technique, wherein to the master of the water flux by film when the osmotic pressure of solution is overcome by excessive hydraulic pressure Want the hydrodynamic resistance that resistance is.In contrast, just infiltration (FO) is based entirely on the technique of infiltration, is driven by infiltration wherein spreading It is dynamic.The factor that water flux is influenced in RO with FO techniques is different, needs different membrane structures to obtain optimum performance in turn.

Invention content

According to one or more embodiments, the method for manufacturing positive infiltration (FO) film may include providing including at least first The support construction of layer and the second layer, is applied to the first layer of support construction to form film supporting layer by material, barrier material is applied Film supporting layer is added to form forward osmosis membrane, and by by the second layer separation of the first layer of support construction and support construction, Discharge forward osmosis membrane；For example, the second layer is removed by stripping, dissolving or in other ways, usually heavier layer.Some can In alternative embodiment, double layer support substrate can be replaced with single layer, which has for thin needed for positive infiltration applications Degree and opening degree, while also having through the intensity and/or thickness needed for conventional membrane producing device operation.

In one aspect, the present invention relates to a kind of films that the supporting layer with enhancing manufactures.The film includes support substrate, enhancing Supporting layer be arranged in support substrate, and active layer be arranged on supporting layer.Supporting layer is by including polymer, nonionic table The solution of face activating agent and ionic surface active agent is made.In various embodiments, polymer is in polysulfones or polyether sulfone At least one, and with the about 10wt% of solution to about 20wt%, preferably from about 12wt% to about 16wt% in cast-solution, with And more preferably from about 13wt% to about 15wt% exists.Nonionic surfactant can be in cast-solution with the pact of solution 0.1wt% to about 1.5wt% exists, preferably from about 0.2wt% to about 1.0wt%, more preferably from about 0.30wt% to about 0.75wt% In the presence of.Ionic surface active agent can in cast-solution with the about 0.05wt% of solution to about 1.5wt%, preferably from about 0.1wt% to about 0.8wt%, more preferably from about 0.15wt% to about 0.45wt% exist.It disclosed below ionic surface active agent With the example of nonionic surfactant.

On the other hand, the present invention relates to a kind of forward osmosis membrane, which includes having first surface and opposite The supporting layer on the first surface of support substrate is arranged in the support substrate of second surface, which includes polymer, ion Surfactant and nonionic surfactant, and the selective layer that is arranged on supporting layer.In various embodiments, Polymer is polysulfones, polyether sulfone or combinations thereof.Nonionic surfactant may include polyoxyethylene (20) cetyl ether or Any other nonionic surfactant disclosed herein can be individual or combination.Ionic surface active agent can be with Including organic acid phosphoric acid ester (for example, alkyl phosphate or amyl acid phosphoric acid ester, such as can be with according to RHODAFAC trade names It obtains).

On the other hand, the present invention relates to the supporting layers for forward osmosis membrane, and wherein supporting layer includes polymer, such as poly- Sulfone, polyether sulfone or combinations thereof；Ionic surface active agent；And nonionic surfactant.In various embodiments, supporting layer It can be manufactured according to any method and formulation disclosed herein.

On the other hand, the method the present invention relates to manufacture for the supporting layer of forward osmosis membrane.This method includes following step Suddenly：Support substrate with first surface and opposite second surface is provided；Polymer solution is cast to the first table of substrate On face, wherein polymer solution include polymer such as polysulfones or polyether sulfone or combinations thereof object, nonionic surfactant, from Sub- surfactant and solvent；Support substrate is led into quenching bath.

In the various embodiments of this method, quenching bath includes solution of the temperature at about 18 DEG C to about 60 DEG C, for spy Fixed embodiment, temperature is at 18 DEG C, 45 DEG C or 60 DEG C.In some cases, quenching bath further includes that one or more surfaces are lived Property agent.Polymer solution can include to account for the polymer of solution about 10wt% to 20wt%, preferably from about 12wt% to 16wt%, And even more preferably about 13wt% to 15wt%.In some embodiments, ionic surface active agent includes organic acid phosphatase Ester, such as those disclosed herein, and can be with the about 0.05wt% to 1.5wt% of solution, preferably from about 0.1wt% is extremely 0.8wt%, and more preferably from about 0.15wt% to 0.5wt% exist.In some embodiments, nonionic surfactant packet Polyoxyethylene (20) cetyl ether or similar compound disclosed herein are included, and can be with the about 0.1wt% of solution extremely 1.5wt% preferably with about 0.2wt% to 1.0wt%, and more preferably exists with about 0.3wt% to 0.75wt%.In various realities It applies in mode, polymer solution further includes water.

In some embodiments, support construction may include double-layer structure.The first layer of support construction can have big In about 50ft³/ft²The frazier air penetrability of min.The material for being applied to the first layer of support construction can be with about 5 and 20g/m²It Between coating apply.Forward osmosis membrane can have the overall thickness less than about 125 microns.Barrier material may include semi-permeable material Material.In at least one embodiment, barrier material may include polymer.In some embodiments, barrier material can be with Including polyamide, polyamide urea, poly- piperazine or block copolymer.Support construction may include polymer paper.Support construction can be with Including PET, polyethylene or polypropylene.For example, substrate can be the thread non-woven paper of polypropylene by polyethylene coating.Support Layer can include generally less than about 30g/m²Material.Backing material can be with about 8g/m²To 20g/m²Between coating apply Add, preferably from about 10g/m²To 18g/m²Between.Supporting layer, backing material and barrier combination weight generally can be in about 20g/ m²And 40g/m²Between.Wet laying process manufacture may be used in supporting layer.

According to one or more embodiments, it may include providing according to this paper institutes to promote the method for positive permeability and separation operation The film for stating method manufacture configures forward osmosis membrane in forward osmosis membrane module, and feedstock solution is led to the side of film and will be driven Dynamic solution leads to the other side of film.

In general, forward osmosis membrane operates under very little or none pressure (for example, 100psi or lower), this is reduce or eliminated With operate relevant compaction problems at elevated pressures present in reverse osmosis membrane system.However, when pressure is less than 100psi When, the desalination degradation of reverse osmosis membrane.When being attempted using conventional reverse osmosis in positive infiltration applications, this causes very low Removal efficiency.Meanwhile forward osmosis membrane needs to design and make in a manner of preventing salt from reversely spreading to feedstock solution from driving solution It makes.Due to ion exchange and Dao Nan effects (Donnan effects), the reversed and positive salt passage in FO films usually enhances.So And providing reduces internal concentration polarization (ICP) and there is the supporting layer of the optimization of good wetability can solve operating Some problems in the case of FO films in those problems.Alternative supporting layer chemicals disclosed herein is suitable for by low pressure It is lower that high removal efficiency is provided and improves total flux to improve the operation of FO films.

In all fields, the present invention relates to the FO films of the supporting layer (that is, the layer for active layer of casting on it) including enhancing. These supporting layers include the blend of polysulfones (PS), polyether sulfone (PES) or both polymer, by the DMF solution of PS or PES It prepares, wherein DMF solution has 0.01% to 5.0% surfactant, with or without other nonsolvent additive (examples Such as water) and with or without salt, such as LiCl, cast on non-woven substrate, which is then immersed in coagulating bath And it rinses in water.In various embodiments, supporting layer may include other similar polymer.In general, by using first Then organic phase coated substrate prepares supporting layer to water phase, discusses in greater detail below.It in other embodiment, can be with With or without the use of supersound process, by using ion or non-in solidification/quenching slot or subsequent potcher Ion surface active improves supporting layer.

The advantages of other aspect, embodiment and these illustrative aspects and embodiment are discussed in detail further below.This Outside, it should be appreciated that aforementioned information and it is described in detail below be all only the illustrated examples of various aspects and embodiment, and be intended to General introduction or the frame of property and feature for understanding aspect and embodiment claimed are provided.Including attached drawing to provide It explanation to various aspects and embodiment and further understands, and attached drawing is comprised in the specification and constitutes the explanation A part for book.Attached drawing is together with the rest part of specification for explaining described and claimed aspect and embodiment party The principle of formula and operation.

Description of the drawings

In the accompanying drawings, identical reference numeral refers generally to identical part in all different views.In addition, attached drawing differs Determine in proportion, on the contrary, emphasis, which is generally placed at, illustrates the principle of the present invention, is not meant as the definition of the limitation present invention.For Clear purpose is not that each component has label in each attached drawing.In the following description, with reference to following attached drawings to this hair Bright each embodiment is described, in attached drawing：

Fig. 1 is the SEM image in the section for the film that one or more embodiments according to the present invention make；

Fig. 2 is the SEM image on the surface for the film that one or more embodiment according to the present invention makes, wherein film is In the case that RHODAFAC at 18 DEG C PS pour casting material and have good surface porosity factor；

Fig. 3 is another film with openr internal structure that one or more embodiments according to the present invention make The SEM image in section, wherein in the case that film is included in BRIJ58 (1%) and 1.5% water, 18 DEG C (left sides) and 45 DEG C The PES (14%) to cast under (right side), and regardless of temperature, macrovoid can be seen with this casting preparation.

Fig. 4 is the SEM image on the surface for another film that one or more embodiments according to the present invention make, and is depicted With the surface of 14% polymer and the supporting layer of 1%PEG 10TDE casting, wherein the film (100kX) in left side is cast at 18 DEG C, And the film (100kX) on right side is cast at 45 DEG C and than it is colder quenching slot in same preparation cast (left side) porosity more It is high；

Fig. 5 A to Fig. 5 C are the SEM images on the surface for the various films that alternate embodiments according to the present invention make；And

Fig. 6 is the SEM image of film, and wherein left-side images are the existing commercialization PS structures for having closely knit network, and right part of flg It seem the film of one or more embodiment casting according to the present invention.

Specific implementation mode

Permeability and separation technique is usually directed to the water flux generated based on permeable pressure head across semipermeable membrane.Due to relative to film Selective resistance water blocking there is the permeability than solute bigger, therefore solute can be removed with envelope and is retained on side.Solute It may not be desirable, therefore removed from technique stream by UF membrane to be purified or desired, in such case They can be concentrated and collected by membrane separation process down.

Film can use in the separating technology of various osmotic drives, such as, but not limited to desalination, waste-water purification and sharp again With the concentration in, FO or PRO bioreactors, the concentration of various liquid flows or dehydration, drug and food-grade application, PRO energy It generates and the energy by permeating heat engine generates.

Polymer film generally includes porous support structure, which provides for selective layer mechanically and structurally props up Support.According to expected application, film can be formed as variously-shaped, including spiral winding, doughnut, tubulose and plain film (sheet).Membrane property should be customized, and to realize ideal performance, and can be changed between concrete application.For example, in FO In being applied with PRO, its porosity and hydrophily can be increased simultaneously by the thickness and curvature for reducing film to enhance separation work The validity of skill, without sacrificing intensity, desalination and water penetration property.

So far, the industry of RO films is in polyethylene terephthalate (PET) branch with polysulfones active coating It is standardized on support layer.PET supporting layers are typically about 4mil thickness, and wherein base weight is about 80g/m², frazier air penetrability is about four ft³/ft²/min.Although firm, PET material typically represents the film raw material of most expensive, and has very to the performance of RO films Less or almost without benefit.When PET is by with support construction in other permeability and separation films, such as FO and pressure retarded (PRO) technique is permeated, film properties are significantly hindered.Therefore, the thickness for reducing support construction may be desired.Attempt to reduce The thickness or weight of backing material typically result in film processing problems, such as fold or corrugation or even web break.Relatively thin branch Support structure may be relevant with the raising of the flux in cost reduction, mass transfer enhancing and film, this is by reducing fluid flowing With solutes accumulation by the resistance of film support, and increase the amount that can be arranged on splitting die active diaphragm area in the block It realizes.

According to one or more embodiments, double base can be provided to promote film to manufacture.Double base may include It will act as the film supporting layer of the film supporting layer of most telolemma product.The film supporting layer of double base can have compared to conventional film branch The thickness that layer reduces is supportted, while the overall thickness needed for film manufacture (including applying and processing selective layer on supporting layer) being provided. In some embodiments, other than film supporting layer, double layer support body may include that removable back sheet is additional to provide Thickness.Removable back sheet can be directed at after film manufactures and support layer separation.In other embodiments, double-layer base Bottom may include keeping complete back sheet after being directed at film manufacture.

Film supporting layer can be the supporting layer of gained film, and it can be mainly sacrificial layer that can remove back sheet, temporarily to branch It supports layer and provides increased thickness to promote film process.Compared with conventional film supporting layer, the film supporting layer of double base usually can be with It is the light base weight layer that thickness reduces.In at least one embodiment, supporting layer can be PET.In some embodiments, it props up Support layer and back sheet can be made of identical material.In other embodiments, they can be made from a variety of materials.It is double The feature of layer substrate can be, in film manufacturing process, be able to together for two layers in terms of intensity, wrinkle resistance and general processing with The property that existing standard PET supporting layers similarly play a role.

In some embodiments, the thickness of back sheet usually can be in about 2mil to about 4mil, and wherein frazier is ventilative Rate is less than about 6ft³/ft²/min.May finally be the top layer of film support construction as described herein thickness it is typically small In about 2mil, wherein frazier air penetrability is greater than about 100ft³/ft²/min.It is micro- that the overall thickness of forward osmosis membrane can be less than about 125 Rice.Supporting layer can include generally less than about 30g/m²Material.Backing material can be with about 8g/m²And 17.5g/m²Between Coating form apply.Supporting layer, backing material and the combination weight on barrier layer generally can be in about 20g/m²And 40g/m²It Between.Top support layer may be used wet laying process, dry-laying process or weaving material and be made.Alternatively, supporting layer It can be made up in the presence of an electric field of deposition such as in electrospinning process.Material may include PET or be commonly used in making The other polymers of pressure-driven film support are made, and can be alternatively designed to hydrophily.In some embodiments In, support construction can be paper, such as polymer paper.In some embodiments, backing material can by PET, polypropylene, PS, polyacrylonitrile or be suitable for generate polyamide, polyamide urea or similar type barrier layer interfacial polymerization supporter its Its porous polymer is made.Hydrophilic additive can be led to backing material.Having described in more detail below can be used for In conjunction with or replace double base film supporting layer example.These layers can be with or without certain additives It is formed, with enhancing or otherwise optimizes the various structural parameters of supporting layer, for example, porosity, curvature, thickness, smooth Degree (for example, best surface condition for accommodating film activity/selective layer).

In film manufacturing process, selectivity or other active layers can be applied to the backing material of substrate.In some realities It applies in mode, semi-permeable layer can be applied as active layer.Semi-permeable layer may include polymer, such as polyamide, polyamides Amine urea, block copolymer, poly- piperazine and/or random copolymer.In some embodiments, double-layer base can be applied to by PS layers The PET supporting layers at bottom.It can be easier to coat than single layer according to the multi-layer substrate of one or more embodiments, because substrate is more It is firm and thicker, to less crease easily and tear.After film processing, it then can detach and remove back sheet.By making With double base, it can use the manufacturing equipment of standard and technology manufacture that there is the film of the supporting layer of thickness reduction.In some realities It applies in mode, separating step can carry out before applying active layer.

According to one or more other embodiments, it is possible to implement be intended to go completely into the bilayer of a part for gained film Substrate, the double base without the use of including sacrifice or other removable back sheets.In these embodiments, it can will prop up Support polymer is cast straight on the one or both sides of warp knit type mesh-supported material.Polyurethane or other adhesives can be used for Supporting layer is attached to lamina reticularis.In some embodiments, support polymer can be PET.Mesh support such as supports Warp knit object can guide fluid to be flowed in the film module of completion.Then film barrier layer can be applied to these support polymerizations On one or two of object coating, final single layer or duplicature are formed, wherein water guide net is as its base portion or core.

According to one or more embodiments, double base can be pre-wetted to improve support polymer and polymer/knit The mass transfer characteristics at object interface.Can use solvent such as NMP, DMF, DMSO, triethyl phosphate, dimethylacetylamide or its The solvent of combination is pre-wetted.More open pore structure can be formed by pre-wetting；Lead to the stifled of hole in polymer supports It fills in less；Enhance effecting porosity of polymer blend membranes by promoting macrovoid to be formed；It improves pore structure and reduces curvature.If made With back sheet can be removed, then back sheet can be removed by separation, may be implemented even to enhance these performances.When use be not intended to by When the double-layer assembly of separation, such as in the case where supporting warp knit type net and PET fabrics, since it for example prevents polymer excessive Backing material is penetrated into, these properties are especially desired to.

According to one or more embodiments, manufacture may include using for the technique of the film of the membrane process of osmotic drive Drive system, with by can the casting machine of polymer deposits in solvent solution be conveyed double layer support material piece or other bases Bottom.It can usually keep tension to reduce fold and corrugated possibility.Double layer support material can be by coarctate two layers Composition so that bottom layer can be subsequently removed or finally be used as membrane fluid interchannel filter.

Double layer support material or other substrates can be transmitted to polymer bringing device, which applies The solution of polymer such as PS in solvent such as DMF.After coating, double layer material can enter quenching bath, wherein polymer It is deposited in substrate.The temperature of quenching bath can change and can influence one or more properties of gained film.At least one In a little embodiments, the improvement performance of forward osmosis membrane may at about 50 °F to 120 °F, preferably from about 60 °F to 113 °F and more Quenching bath temperature in the range of preferably about 100 °F to 110 °F is associated.When using double base, Top-layer Design Method Cheng Yun Perhaps solution fully penetrated will be detached from the layering pressure for being more than about 10psig with precipitating polymeric layer with double layer support material Power.In contrast, the back sheet of double layer material is designed to prevent polymer penetration, to allow two layer of support material in film system It is detached after making.The main purpose of back sheet is to allow existing film machine to transmit needed for forward osmosis membrane very by providing Intensity necessary to thin film when being processed, prevents fold and the corrugation of top layer.Use standard rinsing and film casting equipment Complete the remainder of film production.

According to alternative embodiment, slot composition can be quenched by change and form porous branch in substrate to enhance Support layer.In general, the inversion of phases technique of production PES or PS or similar polymeric support layers can be modified to, to generate for just Infiltration more preferably supporting layer in structure.In one embodiment, 14.5% polysulfones of the film/cast-solution in DMF, wherein With 0.15%RHODAFAC (by the table formed with the aliphatic chain of polyethylene glycol (PEG) chain link for being connected to bound phosphate groups Face activating agent) and water (for example, ion end for being hydrated/stablizing RHODAFAC), wherein being cast in 18 DEG C of quenching slot. There is the network structure of about 400nm thickness, thickness to be enough to reduce the osmotic potential of cross-film by the supporting layer that the supporting layer generates.It is existing There is being limited in technology PS or PES structures be open and is insufficient to allow internal concentration polarization to minimize and flux is made to maximize, This leads to that film supporting layer is made with PS/PES and non-ionic surface active.However, in some cases (for example, using PES), Problem is likely encountered when optimize technique, because it is difficult to from its surface film and particle form middle extraction non-ionic surface active Agent.

Have shown that the conventional inversion of phases technique carried out using ionic surface active agent such as RHODAFAC generation is being supported The centre of layer has the substrate of porous surface and thick network structure, and which increase ICP (referring to Fig. 1 and Fig. 2).In general, having shown Show to generate that there is porous table in the centre of supporting layer using the inversion of phases technique that ionic surface active agent such as RHODAFAC is carried out The substrate in face and thick network structure, which increase ICP.

In one aspect, the present invention relates to allow to control supporting layer form (for example, the hole at control surface and lower face Form) manufacturing process.In various embodiments, cast-solution will include under any circumstance about 8-25%, excellent Select about 14-16% polymer (for example, PS or PES), the ranging from about nonionic surfactant of 0.1-3% (for example, and hydrocarbon chain The polyethylene oxide chain of connection) and optionally, ionic surface active agent and water.In a manufacturing process, which will be by It is applied to substrate or net (such as polyester or polypropylene), Netcom is then made to cross the bath of quenching slot and by 1 to 4 subsequent rinsing Slot.This is verified and generates result shown in Fig. 3 and 4.Typically for forward osmosis membrane, it is expected that making the internal structure of film With characteristics of macro-pore as shown in Figure 3.Have shown that macrovoid by reducing curvature and being dropped by opening wide the inside of film ICP in low forward osmosis membrane, therefore viscous drive solution can be easily close to active layer.

In various embodiments, the present invention relates to ionic surface active agent is put into quenching slot and/or subsequent rinsing In slot, wherein net is immersed in these slots in inversion of phases technique.If using surfactant in being quenched slot, purpose will It is to change the structure for being formed by film.If surfactant is added only in potcher, the main function of surfactant To be except any nonionic surfactant in striping or present on film.In some embodiments, in order to prevent in excess Surfactant in the case of pollute supporting layer, this method can include water wash before last potcher.

Can the example of ionic surface active agent used in the method include：Lauryl sodium sulfate (or with it is hydrophobic Any sulfate of group connection), cetrimonium bromide (or any trimethyl ammonium connect with hydrophobic grouping), and any hydrophobic grouping The carboxylate group of connection or any phosphate being connect with hydrophobic grouping.Hydrophobic chain can pass through Polyethylene Chain and ion official It can group connection.In specific embodiment, ionic surface active agent is included between alkyl tail portion and bound phosphate groups end RHODAFAC with PEG chains.

In the quenching bath that supporting layer casts assembly line, DMF and water coke slurry in preparation of casting.Due to polymer (PS or PES it) is not mixed both when interface is met with water, therefore the interface of polymer and DMF are in upper state.Because at polymer In upper state, when being contacted with water, polymer can be sprung back by hydrone.The distortion of its chain of polymer push polymer further from Water and closer to itself.This will force polymer final itself or the polymer bunching with other entanglement, solidifying from water/DMF solution Gu at perforated membrane.

When polymer is sprung back by water termination, the surfactant in solution is moved in interface to be aligned (wherein PS/ Nonpolar subunit and polarity charged group near PES are towards water/DMF).Surfactant has hydrophilic and hydrophobic part Molecule play the role of stable polarity and nonpolar interface, so that interface is in lower level.Interface can be lower, and polymer is solidifying Gu/to separate into perforated membrane slower.It has been found that slower layering or solidification rate increase the network structure in film, and divides faster Layer leads to macrovoid.Usually it has been shown that instantaneous layering typically results in highly porous substructure (for example, having macrovoid), The substructure have thin, pore surface layer, and postpone layering typically result in it is porous, usually closed pore and without big The substructure of hole, the substructure have intensive relatively thick surface layer.The availability or concentration of the surfactant of interface And structure is to determine interfacial tension and the therefore principal element of the speed of the structure of layering supporting layer.

Straight chain is small and the surfactant of ionic in terms of mitigating interfacial tension more than large-scale nonionic surfactant Effectively.Small ion surfactant can be distorted quickly to be aligned (the nonpolar subunit near wherein PES in interface With polarity charged group towards water).Their small size makes the energy for rotating whole surface active agent molecule be less than large-scale table Face activating agent, such as BRIJ.Large-scale nonionic surfactant (such as BRIJ surfactants) is more difficult to rotate its main polymer chain, Especially because polyethylene oxide chain is very hydrophilic unlike ion.Ionic charge (for example, sulfonate radical or phosphate radical) is by water Molecule fast solvation so that small ion surfactant quickly stable interface.Since small ion surfactant can Quickly to adapt to continually changing environment, therefore they more have in terms of the layering/solidification for slowing down polymer in inversion of phases Efficiency.This can find out (Fig. 1) from the catenet structure of film for using RHODAFAC casting.

One purpose of desired supporting layer casting method is supporting layer of the acquisition with even porous surface, wherein Lower face has a large amount of macrovoid less than about 1 micron.In one embodiment, this is poly- by using 14% in solution Object (for example, PS or PES) is closed to realize, the solution have DMF, 0.1-3% nonionic surfactant (for example, BRIJ or with Another polyethylene oxide of alkyl chain link) and 0.1-3% ionic surface active agents.It is molten according to this regardless of cast temperature The internal structure for all experimental films that liquid is formed all is unlimited, and has many macrovoids.

In general, highly porous surface is critically important, because they increase the driving solution side for being transported to film from feed water Water transmission speed.As shown in Figure 4, it appears that it is very big to be quenched influence of the temperature of slot to surface porosity factor, is different from 18 DEG C On the surface for the film that ionic surface active agent (Fig. 2) is formed, this may be at least partly because non-ionic surface active Agent fails to stablize DMF/ water and polymer interface.Using the quenching slot at 18 DEG C, PES layerings are so fast so that polymer It is shunk from the water of entrance and is shrunk to the solid block with few hole, although hole is big.Compared at a lower temperature, in higher temperatures The lower surface of degree formed have it is more porous because polymer with more energy to keep water-soluble/DMF environment, this subtracts The slow rate of polymer solidification simultaneously causes to form more holes at surface.Surfactant is more effective and available, reduces It is better in terms of the energy of interaction, and solidification/precipitation of PS is slower.It has been shown that fast during supporting layer is formed Rapid hardening, which is consolidated/precipitated, may cause top surface to include closelypacked particle, this may be considerably less or large-scale in surfactant (referring to Fig. 5) occurs in the case that nonionic surfactant (for example, BRIJ 58) concentration is too small.Fig. 5 A to Fig. 5 C indicate to use The scanning of a surface for the film support that in DMF prepared by 14%PES, DMF have 1%BRIJ 58 (2,000 ×) (Fig. 5 A, a small amount of Grain), 0.8%BRIJ 58 (8,000 ×) (Fig. 5 B, many particles) and 0.5%BRIJ 58 (400 ×) (Fig. 5 C, many Grain).

This stabilisation reduces interfacial energy, and it reduce the rates of polymer layering/solidification, and which prevent granulateds At and even if at cold temperatures formed porous surface (see, for example, Fig. 2).By in being quenched slot using it is small-sized from Sub- surfactant, rather than cast-solution, we can induce porous surface in the case of no particle, while keep main The internal structure to be made of macrovoid.

Stable film can be played in a small amount of ionic surface active agent in being quenched slot water during former seconds in hierarchical process The effect at the interface at surface.However, when water permeates film surface towards substrate/net, the water intermediate ion with PES interfacial contacts The concentration of surfactant will reduce, because surfactant will focus on the surface of film, to reduce the interface at film surface Energy.Layering in the less ionic surface active agent that can be used for stablizing internal structure formation, film will faster make Macrovoid must be formed.(it can be by optimum experimental to adapt to spy for a certain concentration of ionic surface active agent in being quenched slot Fixed application) under, macrovoid still can under the surface it is rectangular at.Surface formed it is surfactant-stabilized can be by slowing down point Layer/solidification rate helps prevent the formation of surface particles.This will also allow porous surface at cold temperatures.

Show that more nonionic surfactant can reduce particle and be formed, but too many surface can be left on film/quenching slot and lived Property agent.Polyethylene glycol PEG in other words, is the water of some nonionic surfactants used in cast-solution disclosed herein Soluble components.PEG load-bearing surfaces activating agent may will present LCST behaviors, therefore the first quenching slot is made to be 18 DEG C rather than 45 DEG C To be beneficial.Surface porosity factor can be reduced by having shown to cast at colder temperatures (see, for example, Fig. 4).By in being quenched slot Using ionic surface active agent, colder quenching slot can be molded into the case of not sacrificial surface porosity.

In various embodiments, PS/PES film supports have been cast using only 2% BRIJ O20, which create with Less particle and macroporous supporting layer at surface.However, the supporter cast with 1% BRIJ O20 is in support layer surface In large part have many particles.When using 2%BRIJ in preparation of casting, it is quenched in slot and would generally leaves table on film Face activating agent, this needs to stop casting process so that can empty and recharge quenching slot.By adding surface to quenching slot Activating agent can faster dissolve nonionic surfactant, form " cleaner " film.Ionic surface active agent will help to dissolve non- Ionic surface active agent so that can be changed places by the blowing water capacity and remove nonionic surfactant.

In some embodiments, if in being quenched slot use ionic surface active agent, may hinder inversion of phases (because For macroporous formation can be limited)；However, surfactant is added in flushed channel that still can be below, it will be non-with help Ionic surface active agent is washed off from film.Water wash can be used to remove the two kinds of surface on film in the ending of foudry line Activating agent.Generally, particle is formed in order to be limited in film support layer surface, ion surface active can be used in being quenched slot Agent, or in cast-solution ion table can be added using additional nonionic surfactant, while to subsequent rinse bath Face activating agent.

The present invention enhances casting technique using additional technique and removes extra surfactant.Generally, surface-active Agent is not easy to wash off after inversion of phases and in subsequent rinse bath due to its size and non-ionic nature.Wash off surfactant It is critically important, because extra surfactant can stay on casting machine, thus the phase of the film produced on same roller after destroying Conversion.It is adversely affected moreover, the surfactant left is likely to the formation of the active layer on the supporting layer to casting. Using the solubility that can improve surfactant and other impurities is ultrasonically treated, to improve the quality of film.In addition, using ultrasound Processing allow it is freer when selecting surfactant because now can inappropriate surfactant before use because The ability that improvement is removed it.

As disclosed previously, cast-solution usually sprays on polyester webs, and carries out inversion of phases by quenching slot.Quenching Slot or subsequent rinse bath will be equipped with Probe Ultrasonic Searching wave instrument, or be equipped with another sonication techniques and it is made to become effective large-scale Ultrasonoscope.It is ultrasonically treated and will focus on the place that film passes through slot, to improve the validity of ultrasonoscope.Supersound process makes substance Faster dissolve in the liquid phase.Polysulfones or polyether sulfone can be plasticized by the supersound process in inversion of phases bath, be made near the surface on surface layer Form more reticular structures.

According to one or more embodiments, finished film may include selective blocking, such as semi-permeable three-dimensional polymer Network, including such as aliphatic or aromatic polyamide, aromatic polyhydrazide, polybenzimidazoles ketone, poly- table amine amide, poly- table Amine/urea, polyamide urea, polyethyleneimine/urea, the poly- furans of sulfonation, polybenzimidazoles, poly- piperazine isophthaloyl amine, polyethers, polyethers- Urea, polyester or polyimides or its copolymer or mixture any in them.In some embodiments, selectivity blocking can To be aromatic series or non-aromatic polyamide, such as phthalyl (for example, phenyl-diformyl or paraphenylene terephthalamide) halogen, equal benzene Or mixtures thereof the residue of three formyl halides.In another embodiment, polyamide can be phenylenediamine, benzene triamine, polyetherimide, The residue of the residue and phenylenediamine of three formyl halide of residue or equal benzene of piperazine or poly- piperazine.Selectivity blocking can also include equal benzene The residue of three formyl chlorides and m-phenylene diamine (MPD).In addition, selectivity blocking can be the reaction production of pyromellitic trimethylsilyl chloride and m-phenylene diamine (MPD) Object.The blocking of being typically chosen property is characterized in that being enough to assign the desired thickness for refusing salt and permeable property, while usually minimizing Whole film thickness.In some embodiments, the average thickness selectively stopped is about 50nm to about 200nm.Desirably it hinders The thickness of barrier receives limitation as far as possible, but also sufficiently thick, can prevent coating surface from generating defect.It is semi-permeable for pressure-driven The practice that the PA membrane of film is formed can inform how to select suitable blocking film thickness.Selectivity blocking can be for example, by Interfacial polymerization is formed on the surface of porous supporting body.

It may be suitable as including poly- (ether sulfone according to the other polymers of the porous supporting body of one or more embodiments Ketone), poly- (ether ethyl ketone), poly- (phthalazone ether sulfone ketone), polyacrylonitrile, polypropylene, polyvinyl fluoride, polyetherimide, acetate fiber Element, cellulose diacetate and Triafol T polyacrylonitrile.

In certain embodiments, supporting layer is PS bases or PES bases comprising certain additives are (for example, enhancing hole shape At surfactant) and be free of other additives commonly used in the art.Following table 1 lists that can be adapted for different application all Such as improve flux and/or improves many examples of the support layer formulation of solute removal efficiency.Generally, various polymer solutions (for example, PS or PES) the various surfactant additives of doping, to form phase inversion membrane, and without using polyvinylpyrrolidone (PVP) or Polyethylene glycol (PEG).The some of additives used include different surfaces activating agent, e.g., sorbester p17, polysorbas20 and 80, ten Sodium dialkyl sulfate (SDS), cetyl trimethylammonium bromide (CTAB) and triton x-100, as pore-foaming agent, to change film Form.It is desirable that surfactant will not remain in the surface of film so that active layer can be applied to surface.The doping of proposition The preparation of solution is also unique, be unique in that it includes different surfaces activating agent, different polymer, different weight percentage it is poly- Object, the surfactant additive of different weight percentage, different solvents are closed, and are free of other additions in addition to surfactants Agent (for example, PVP or high molecular weight PEGs).These preparations generally include DMF and/or NMP as solvent, and many further includes For example, about 0.1 to about 1.0wt%, preferably about 0.25 to about 0.75wt%, more preferably about 0.35 to about 0.45wt% water. Generally, the surfactant additive of solution helps to form finger-type structure, to improve the wetting of current forward osmosis membrane supporting layer.Separately One target is to reduce the internal concentration polarization of the forward osmosis membrane made according to the present invention and improve flux.By developing finger-type structure This target has been realized with thin skin layer, next this improves the osmotic efficiency of driving solution again.

Table 1.

Typical TFC forward osmosis membranes are mainly made of PS, and PS is hydrophobic polymer.The hydrophobicity of PS and the PS supports of film The constraint pore structure of layer causes the driving solution-wet of film back side bad.Water flux from feed side to driving side reduce with The concentration of driving solution near the active layer of supporting layer contact.In addition, supporting layer and the constraint pore structure of substrate make greatly Amount driving solution is difficult to reach near the side of active layer, and is difficult to concentrate the driving solution near active layer again (this determines the poor driving force of infiltration).This will cause internal concentration polarization, internal concentration polarization that can reduce the infiltration of positive osmosis system Poor efficiency.

The surfactant of the good candidate of the pore-foaming agent or additive that are suitable as in PS/PES and DMF solution will With particular application change, typically there is low molecular weight and be easy the surface washed off in casting machine potcher during manufacture Activating agent.Additionally, it is desirable to surfactant be in coating processes when staying the when of remaining in supporting layer not interfere with work on a small quantity Formation, uniformity and the quality of property layer.

Using non-solvent (water) phase inversion and by PS or PES, surfactant and N-N dimethylformamides (DMF) group At doped solution generate typical film supporting layer.The surfactant of good results includes following surfactants after tested： Qula leads to (octylphenol ethoxylate), and such as Qula leads to X-305, Qula leads to X-405, Qula leads to X-705；TERGITOL is (secondary Alcohol ethoxylate), such as TERGITOL 15-S-5, TERGITOL 15-S-9, TERGITOL 15-S-30；BRIJ (ethoxies Base fatty alcohol), such as BRIJ L4, BRIJ C10, BRIJ O20；BRIJ 58,50 (cocamidopropyl propyl amides of MACKAM LSB Hydroxyl sulfo betaine)；And low molecular poly of the molecular weight between 100 to 2000.The initial film of generation uses Manual casting method is formed, and solution is solidified at 18 DEG C, 45 DEG C and 60 DEG C casts under water-bath.PS/PES concentration can 10wt% extremely Change between 20wt%, best result occurs in about 13wt% between about 15wt%.The concentration of surfactant can be About 0.1wt% changes between 8wt%, and best result occurs in about 2wt% between about 4wt%.Solution temperature can be Change between about 15 DEG C to about 45 DEG C.Coagulation bath temperature can change between about 12 DEG C to about 65 DEG C, wherein higher solidification Bath temperature will cause higher CWF and higher FO flux.

Some experiment in, under about 18 DEG C and about 45 DEG C of coagulation bath temperature with 2% surfactant (BRIJ O20, TERGITOL 15-S-9 and TERGITOL 15-S-30) cast membrane in the production line.All films cast in front and retouch In the double base stated, wherein the second layer removes after pouring, and net water flux is caused to improve, for the about 6- of conventional PS supporters 10 times.After being coated in active layer on new PES supports preparation, when 50,000ppm NaCl solutions are used as raw material and 1.8 When mole of ammonium carbonate solution is used as driving solution, the existing PS supporting layers of flux ratio improve 40 to 50%.It is soaked with 5%IPA On performance without influence.

Fig. 6 shows the SEM image of film.Image to left is the existing commercialization PS structures for having closely knit network, Image to right It is the new engine casting PS/PES films according to the present invention with the finger-type structure developed completely.Preparation includes 2%BRIJ O20, Wherein coagulation bath temperature is at 45 DEG C.

FO tests have been carried out with wetting technique and without wetting technique to the above-mentioned PS/PES films manufactured with casting machine.Below TFC FO film properties do not have difference in the case that the display of table 2 is with or without wetting technique.

Table 2.

In an alternative embodiment, supporting layer, which is the surfactants of DMF and 0.01% to 5%, has other additives or without it PS, PES in solution in the case of his additive or both combination.Such as water has salt or salt-free such as lithium chloride (LiCl), it casts in substrate such as nonwoven polyester (or polypropylene), be then immersed in solidification/quenching bath and rinse in water. In general, supporting layer disclosed herein will coat water phase first, be then coated with organic phase, to be formed for the selection layer that is just permeating and Most telolemma.

Water phase can be by m-phenylene diamine (MPD) (MPD), m-xylene diamine, the hexamethylene -1,3,5- three of 1wt% in water to 10wt% Amine, benzene -1,3,5- triamines, 4H-1,2,4- triazoles -3,4,5- triamines, piperazine, p-phenylenediamine, and combinations thereof, having surface-active It is formed in the case of agent or surfactant-free, such as those disclosed herein.Will to following additives or mixtures thereof (individually), And sour (for example, acetic acid, camphorsulfonic acid, methanesulfonic acid, trifluoroacetic acid, nitric acid, hydrochloric acid and citric acid) is added to water phase, with control The removal efficiency of flux and FO films, including：Triethylamine, N- methyl-diethyl-amines, N, N- diethyl ethanamines, trimethylamine, N, N- diisopropyls Base methylamine, N, N, N ', N '-tetramethyls diaminomethane, N, N, N ', N '-tetramethylethylenediamines [(lignocaine) methyl] diethyl Amine, hexa, triethylenediamine, tri- azepine -7- phospha-adamantanes of 1,3,5-, isopropylamino -2- dimethylaminos Base ethane, three (2- amino-ethyls) amine, three (3- aminopropyls) amine, 2,2'- diamino-Ns-methyl-diethyl-amine, N, N- diethyl Ethylenediamine, N, N', N "-trimethyldiethylene triamine, N, N- dimethyl-ethylenediamines, (dimethylamino) -1- propylamine, N, N- are bis- [3- (methylamino) propyl] methylamine, N '-(2- amino-ethyls)-N'- methyl ethane -1,2- diamines, dimethylamine, ethyl dimethylamine, Diethylamine, ethylenediamine, 1,4- diaminobutanes, N- methyl ethylenediamines, N, N'- dimethyl-ethylenediamines, N- ethyl isopropylamines, N- are different Propyl-N- propylamine, bis- [2- (methyl ammonium) ethyl] ammoniums, N, bis- (3- the aminopropyls) -1,3- propane diamine of N'-, bis- (3- aminopropans Base) amine, tetraethylenepentamine, ethanol amine, 2- [2- amino-ethyls (2- ethoxys) amino] ethyl alcohol, N- (3- aminopropyls) diethanol Amine, triethanolamine dimethylaminoethanol, triethanolamine (such as 4%), N methyldiethanol amine, N- ethyldiethanolamines, N- Butyl diethanolamine, diethanol amine, 2- [2- (dimethylamino) ethyoxyl] ethyl alcohol, N- phenyldiethanol-amines, three second of nitrilo- Sour, bis- (2- chloroethyls) methylamine hydrochlorides, 1,4- diazabicyclos [2,2,2], N, N, N', N'- tetramethyl -1,3- butanediamine (TMBD), N, N, N ', N, N, N', N'- tetramethyl -1,6- hexamethylene diamines, N, N, N', N ", N " '-five methyl diethylentriamines.Its He includes at additive：Quaternary ammonium cation chemical combination object and its surfactant, such as Cocoamidopropyl betaine (CAPB) and ten Poly- (ethylene oxide) ammonium chloride of dialkyl methyl；Amine oxide surfactant, such as lauryl dimethyl amine oxide, N, N- diformazans Base dodecyl amine n-oxide, N, N- dimethyl tetradecyl amine N- oxides and 3- laurylamides-N, N' dimethyl Propyl amine oxide (LAPAO)；And organic phosphorus compound, such as four (methylol) phosphonium chlorides and bis- [four (methylol) Phosphonium] sulfuric acid Salting liquid.

Organic phase may include having mesitylene cosolvent or without mesitylene cosolvent, isopar G or ring Pyromellitic trimethylsilyl chloride (TMC) (0.1wt% to 0.3wt%) in hexane.It can be used in the case where having TMC or without TMC His monomer, such as m-phthaloyl chloride, 1,3,5- hexamethylene, three formyl chloride, 1,2- hexamethylenes, two formyl dichloro, anti-form-1,4- rings Hexane dimethyl chloride, benzene -1,3,5- triisocyanates and 1,3- phenylene diisocyanates.

Generally, above-mentioned additive and surfactant will be added to due to reacting the cross-linked network formed between MPD and TMC Network.Some additives react with TMC and are formed in active layer covalent bond, some other formation hydrogen bonds and ionic bond.Other Additive and surfactant form ionic bond with carboxylic acid or form hydrogen bond with Nomex.These additives and surfactant Presence change the wetability of supporting layer and reduce flux in RO tests and due to forming secondary or physical bond in the hole of active layer, The removal efficiency of active layer is improved in FO tests simultaneously.

Generally, it is hardly formed the efficient and functional supporting layer for FO films.With report before on the contrary, by by PS It is undesirable to be dissolved in the finger-like micro-structure formed in pure solvent or solvent mixture.Although finger-like micro-structure can improve film S parameter and reduce driving solution osmotic potential loss, but this micro-structure resist hydraulic pressure robustness be of problems.Though Be not true to type in FO techniques so, but it sometimes appear that higher hydraulic pressure (for example, about 100 to 250psi, substantially less than typical case RO Pressure), and observe that the active layer being disposed thereon caves in, especially there is the macroporous PES bases supporter of big finger-like.Cause This, it has been found that support casting preparation can improve FO film properties, and support casting preparation generates the combination of finger-like and the network architecture Micro-structure, when by high hydraulic pressure (for example, 100-250psi), the reticular structure under surface layer is enough to support active layer, and away from More finger-like micro-structures farther from surface layer, allow drive solution in barrier is than complete mesh architecture it is less more Supporter is passed through well, reaches active layer.Changed during inversion of phases using various supporting layer casting preparations described herein and is poured Cast solution kinetics so that supporting layer has openr internal structure.The supporting layer of these modifications improves FO performances, simultaneously It is thicker, more closely knit also subject to hydraulic pressure more higher than normal fluid pressure, and without seeking help from supporting layer thicker, more closely knit in RO films Supporting layer it is very unfavorable for FO performances.

In various embodiments, cast-solution includes with nonionic surfactant (for example, polyoxyethylene (20) 16 Ether, such as BRIJ 58) and anion surfactant (for example, polyoxyethylene nonylphenol ether phosphate, such as RHODAFAC RE610 the polysulfones and water and DMF) combined.In some embodiments, cast-solution include it is following in it is one or more： The polysulfones of concentration about 10% to 17%, preferably from about 12% to 15%, more preferably from about 13.5% to 14.5%；Concentration about 0.01% to 1.0%, preferably from about 0.05% to 0.50%, more preferably from about 0.08% to 0.15% anion surfactant (for example, RHODAFAC or similar)；Concentration about 0.01% to 2.0%, preferably from about 0.05% to 1.5%, more preferably from about 0.08% to 1.0% nonionic surfactant (for example, BRIJ 58 or similar, such as those disclosed herein)；Concentration about 0.01% To 2.0%, preferably from about 0.05% to 1.5%, more preferably from about 0.08% to 1.0% water；About 10 DEG C to 50 DEG C, preferably from about In the DMF solution prepared at 15 DEG C to 40 DEG C, more preferably from about 20 DEG C to 35 DEG C, about 5 DEG C of temperature is extremely for coagulating bath (for example, quenching slot) 70 DEG C, preferably from about 10 DEG C to 60 DEG C, more preferably from about 12 DEG C to 50 DEG C.In some embodiments, nonionic surfactant can To be the combination of one or more nonionic surfactants, and may include hydrophobic part such as alkyl chain and hydrophilic Part such as PEG chains.In some embodiments, cast-solution be in DMF solution polysulfones and one or more nonionic tables The combination of face activating agent, wherein nonionic surfactant provide openr internal structure.In various embodiments, it retouches above The cast-solution stated generates surface holes within the scope of about 10-110nm, about 33-70 μm of net water flux about 80-210GFD and thickness Film supporting layer.

According to one or more embodiments, the feature of supporting layer can be that thickness is enough to be in manufacture and during use film Supporter and structural stability are provided, while usually minimizing whole film thickness.In some embodiments, polymer supports Average thickness be about 10 μm to about 75 μm.General, it is desirable to be that supporter is as thin as possible, but does not damage the matter of support surface Amount, influences the interfacial polymerization on barrier layer.Supporting layer is more smooth, and the commonly required backing material thickness of the standard is smaller.At least In some embodiments, which is less than about 40 μm.In some embodiments, porous supporting body has the first side (active side) With the second side (support-side), there are more than first a holes, the second side to have more than second a holes for the first side.In some embodiments, A hole more than first and more than second a holes are fluidly coupled to each other.In one embodiment, polymeric additive is in porous supporting body Middle dispersion.Additive can enhance hydrophily, antiscale, intensity or other desired properties, for example, can be added about to PS The PVP of 0.1-1%, the hydrophily of enhancing structure.

According to one or more embodiments, thin-film composite membrane may include the open support with the first side and the second side There are more than first a holes, the second side to have more than second a holes for body, the first side, wherein a hole is averaged more than essentially all first Diameter is in about 50nm between about 500nm, and the average diameter in a hole more than essentially all second is between about 5 μm to about 50 μm. The purpose of top layer is to allow that forms high quality blocking by interfacial polymerization or other sedimentations, and is carried for very thin barrier layer For mechanical support.The purpose of support construction remainder is as open as possible and as non-warping as possible, while as thin as possible.Direction The macropore of bottom can promote this purpose.

In some embodiments, in the case where 25 DEG C, 1.5M NaCl drive the operating condition of solution and DI feedstock solutions, film Flux can be at about daily 15 gallons every square feet to about daily between 25 gallons every square feet.The high throughput shows thin , open, porous and low curvature supporting layer the resistance of film support construction is entered to be carried for flux to driving solutes accumulation reducing For osmotic pressure form driving force in terms of validity.The partly cause of the high throughput lies also in the water penetration on barrier layer.

According to one or more embodiments, forward osmosis membrane can be formed by generating supporting layer first.In some realities It applies in mode, the flimsy material backing layer less than about 30 microns can coat the dimethyl formamide solution of about 12.5%PS.It is relatively low dense The PS of degree can be used for further improving forward osmosis membrane property, including flux.In some embodiments, polysulfones coated weight can be with Generally less than about 16g/m², to minimize influence of the supporting layer to diffusion.Typical RO fabric in about 3.9 Mill of thickness is carried on the back Applying supporting layer on layer can make the most preferably positive permeation flux of flux ratio much smaller.

Then, the supporting layer precursor of gained can immerse in room temperature water, make polymer that inversion of phases occur.More than 90 °F At a temperature of immerse can be used for improve supporting layer pore diameter characteristics.This can generate thin, micropore with built-in network, open Support construction provides the intensity for rolling and handling for polymer.Then it can apply active layer to support construction.With activity The example that layer coats the support construction is will to support to immerse in the solution containing polyamide or other expectation active materials.At one In embodiment, support construction can be immersed at room temperature in 3.4% 1-3 phenylenediamine aqueous solutions.The concentration of solution can root According to the desired characteristic variation of the active layer of application.The duration of immersion can also change.In some embodiments, when continuing Between can be less than about 5 minutes.In a particular implementation, the duration of immersion can be about 2 minutes.It can will be extra Solution removed from the surface of film, such as removed with roller or air knife.

Then, film of short duration can immerse another solution, pass through the knot of diamines in water phase and such as nonaqueous phase acid chloride Close the polymerization that polyamides amine removal layer is caused on the surface that these mutually merge in backing material.In some embodiments, film can soak Enter solution about 2 minutes.In one embodiment, can be existed at room temperature using 98%1,3,5 benzene, three formyl chloride 0.15% solution in C or G.Then film can be removed, is allowedBe, for example, less than for a period of time after five minutes can be with It is evaporated from film.In some embodiments, the duration of evaporation step can be about 2 minutes.In some embodiments, The form that dipping process may be used is immersed, such as wherein substantially there was only the technique that the surface of film is contacted with solution.At other In embodiment, entire film can be immersed in bath.In some embodiments, the combination of these technologies can be used, such as By the different sequences for immersing step.

According to one or more embodiments, various technologies disclosed herein can be used for making for positive infiltration applications Film.According to one or more embodiments, various technologies disclosed herein can be used for making for being related to pressure retarded osmosis Application film.In some embodiments, pressure retarded osmosis generally may relate to from such as dense driving solution of two kinds of solution Salinity difference between dilute working fluid obtains osmotic engine or salinity gradient energy.In pressure retarded osmosis, it can incite somebody to action Solution is driven to introduce in the balancing gate pit of the first side of film.It in some embodiments, can be according to driving solution and dilute workflow Permeable pressure head between body presses at least part of driving solution.Dilute working fluid can be introduced in the second side of film.It is dilute Working fluid can generally move through film by infiltration, therefore increase the volume of the pressure driving solution side of film.With pressure It is compensated, turbine can be made to rotate, generate electric power.Then dilute driving solution of gained can be handled, is such as detached, For reusing.In some embodiments, low-temperature heat source such as industrial waste heat can be used for or promote pressure retarded osmosis system System or technique.

Some illustrated embodiments have been described, it will be understood by those skilled in the art that aforementioned be merely illustrative and It is unrestricted, only present by way of example.Those of ordinary skill in the art are contemplated that many modifications and other embodiment, And it is contemplated as falling within the scope of the present invention.Particularly, although many in embodiments set forth herein is related to method action or system The specific combination of element reaches identical mesh it will be appreciated that these actions or these elements can be combined otherwise 's.

It will be understood by those skilled in the art that parameter described herein and configuration are exemplary, actual parameter and/or match Set concrete application used in system and technology depending on this paper.Those skilled in the art will also be understood that or can be using only normal The equivalent of the specific implementation mode of the present invention is determined in the case of rule experiment.It is understood, therefore, that implementations described herein Only present by way of example, it within the scope of the appended claims and their equivalents, can be with the side other than specific descriptions The formula practice present invention.

Claims

1. a kind of forward osmosis membrane, including：

Support substrate, the support substrate have first surface and opposite second surface；

Supporting layer, the supporting layer are arranged on the first surface of the support substrate, the supporting layer include polymer, Ionic surface active agent and nonionic surfactant；And

Selective layer, the selective layer are arranged on the supporting layer.

2. forward osmosis membrane according to claim 1, wherein the support one polymer include in polysulfones or polyether sulfone extremely Few one kind.

3. forward osmosis membrane according to claim 1, wherein the supporting layer nonionic surfactant includes polyoxyethylene (20) cetyl ether.

4. forward osmosis membrane according to claim 1, wherein the supporting layer nonionic surfactant includes organic acidity Phosphate.

5. a kind of supporting layer for forward osmosis membrane, including：

Polymer, the polymer include at least one of polysulfones or polyether sulfone；

Ionic surface active agent；And

Nonionic surfactant.

6. supporting layer according to claim 5, wherein the nonionic surfactant includes polyoxyethylene (20) 16 Alkyl ether.

7. supporting layer according to claim 5, wherein the ionic surface active agent includes organic acid phosphoric acid ester.

8. a kind of method of supporting layer of manufacture for forward osmosis membrane, the described method comprises the following steps：

Support substrate with first surface and opposite second surface is provided；

Polymer solution is cast on the first surface of the substrate, wherein the polymer solution includes：Including poly- Polymer, nonionic surfactant, ionic surface active agent and the solvent of at least one of sulfone or polyether sulfone；

The support substrate is led into quenching bath.

9. according to the method described in claim 8, wherein, the quenching bath is included in about 18 DEG C to about 60 DEG C of solution.

10. according to the method described in claim 8, wherein, the polymer solution includes accounting for the solution about 10wt% extremely The polymer of 20wt%.

11. according to the method described in claim 8, wherein, the polymer solution includes accounting for the solution about 13wt% extremely The polymer of 15wt%.

12. method according to any one of claims 8, wherein the polymer solution includes accounting for the solution about 0.05wt% extremely The ionic surface active agent of 1.5wt%.

13. according to the method described in claim 8, wherein, the polymer solution includes the about 0.15wt% for accounting for the solution To the ionic surface active agent of about 0.5wt%.

14. according to the method described in claim 8, wherein, the polymer solution includes accounting for the solution about 0.1wt% extremely The nonionic surfactant of 1.5wt%.

15. according to the method described in claim 8, wherein, the polymer solution includes accounting for the solution about 0.3wt% extremely The nonionic surfactant of 0.75wt%.

16. according to the method described in claim 8, wherein, the polymer solution further includes water.

17. according to the method described in claim 8, wherein, the ionic surface active agent includes organic acid phosphoric acid ester.

18. according to the method described in claim 8, wherein, the nonionic surfactant includes polyoxyethylene (20) 16 Alkyl ether.